Messages in this thread | | | From | Mathias Krause <> | Date | Tue, 14 Feb 2017 17:40:40 +0100 | Subject | Re: [PATCH 1/6] x86: drop unneded members of struct cpuinfo_x86 |
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On 14 February 2017 at 17:17, Borislav Petkov <bp@alien8.de> wrote: > On Sun, Feb 12, 2017 at 10:12:07PM +0100, Mathias Krause wrote: >> Those member serve no purpose -- not even fill padding for alignment or >> such. So just get rid of them. > > Well, almost. You need the wp_works_ok removal patch too, otherwise you > have the 3 bytes hole below.
Heh, indeed! But only since commit 79a8b9aa388b ("x86/CPU/AMD: Bring back Compute Unit ID") ;)
> But the wp_works_ok goes away too so I guess that's fine. > > $ pahole -C cpuinfo_x86 vmlinux > struct cpuinfo_x86 { > __u8 x86; /* 0 1 */ > __u8 x86_vendor; /* 1 1 */ > __u8 x86_model; /* 2 1 */ > __u8 x86_mask; /* 3 1 */ > char wp_works_ok; /* 4 1 */ > __u8 x86_virt_bits; /* 5 1 */ > __u8 x86_phys_bits; /* 6 1 */ > __u8 x86_coreid_bits; /* 7 1 */ > __u8 cu_id; /* 8 1 */ > > /* XXX 3 bytes hole, try to pack */
The cu_id member is "new". Without it there would be no hole. But, yeah, without wp_works_ok everything's fine again.
Cheers, Mathias
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